Disabling automatic keyframe creation...

Is there a way to adjust a value without it creating a keyframe? Often I'm just experimenting with values, playing it back to see how it looks, etc. So I would then end up with a tonne of keyframs at different times, it's a mess.

It would be cool if I could adjust a value no matter where I'm at on the timeline, and only create a keyframe if I tell it to. This is exactly how After Effects works.